The present invention relates generally to needles useful in the dispensing of plastic fasteners and more particularly to a novel such needle.
Plastic fasteners of the type commonly used, for example, to attach merchandise tags or other items to articles of commerce, such as articles of clothing, are well-known and are widely used in the retail industry. Typically, such fasteners comprise an elongated unitary plastic member having a first end shaped to define a cross-bar (also commonly referred to as a "T-bar"), a second end shaped to define a paddle (or a second cross-bar), and a thin flexible filament portion interconnecting the cross-bar and the paddle. The cross-bar is typically sized and shaped to be inserted first through a merchandise tag and then through the article of commerce. The paddle is typically sized and shaped to prevent the tag from being pulled off the filament portion.
Typically, such fasteners are mass-produced by a molding process in either one of two different forms known as fastener stock. One type of fastener stock, which is disclosed in commonly-assigned U.S. Pat. No. 3,103,666 and which is incorporated herein by reference, comprises a plurality of fasteners joined together at their respective cross-bars by an orthogonally disposed runner bar. The other type of fastener stock, which is disclosed in commonly-assigned U.S. Pat. No. 4,955,475 and which is incorporated herein by reference, comprises a plurality of fasteners arranged in an end-to-end alignment, the heads and opposite ends of successive fasteners being joined together by severable connectors so as to form a continuously connected fastener stock.
The dispensing of individual fasteners from fastener stock into desired articles of commerce is typically accomplished using an apparatus commonly referred to as a "tagger gun." Examples of tagger guns are illustrated in commonly-assigned U.S. Pat. Nos. 5,320,269, 5,024,365, 4,121,487 and 4,456,161, all of which are incorporated herein by reference. Typically, a tagger gun includes (a) a hollow needle having a longitudinal slot extending across its length; (b) means for separating an individual cross-bar from the remainder of the fastener stock; and (c) means for feeding the individual cross-bar through the hollow, slotted needle and the desired article of commerce. (Connections, if any, between the paddles of a pair of adjacent fasteners are severed by pulling the tagger gun away from the article of commerce after the cross-bar of one of the fasteners has been inserted thereinto.)
Often, the aforementioned separating means comprises a knife element which is used to sever the severable connector located between a cross-bar and the runner bar or between adjacent cross-bars. In some instances, the knife element is attached to or is incorporated into the structure of the hollow, slotted needle in such a way that the severable connector is cut as a cross-bar is loaded into the hollow, slotted needle. An example of the foregoing is illustrated by U.S. Pat. No. 4,333,596, which is incorporated herein by reference. In this patent, a high strength needle assembly with a sharpenable cutting edge is disclosed, the assembly including a shank part having a tip and cylindrical hollow portion, a base part having a central bore and a knife part. The central bore has first and second sections, the first section having an inner diameter equal to the outer diameter of the cylindrical portion, such that the shank can be inserted therein and secured thereto by an adhesive. The second section has an inner diameter equal to the inner diameter of the cylindrical portion. The knife part includes a body portion with a cutting edge on one end and a protrusion on the other end, the protrusion being adapted to be received within and secured to a recess adjacent the second section of the bore. The knife part extends beyond the base in a direction substantially parallel to the axis of the base such that the cutting edge is accessible for re-sharpening.
Another example of a needle in which a knife element is incorporated thereinto is disclosed by U.S. Pat. No. 5,307,975, which is incorporated herein by reference. In this patent, there is disclosed a needle for use as part of a fastener dispensing tool, the needle being made from a single sheet of metal by a stamping and/or rolling technique, and comprising an elongated, generally cylindrical, hollow, slotted member having a stem portion and a base portion. The stem portion terminates at its front end in a relatively sharp tip. The base portion, a portion of which is sized and shaped for insertion in an opening in the nose of the tool, includes a pair of upwardly extending, spring tabs bent outwardly away from each other. A first portion of one of the tabs is sized and shaped to releasably engage a recessed area formed in the nose of the tool to prevent unintended removal of the base potion from the opening and to limit rearward insertion of the base portion into the opening. A second portion of the same tab is sized and shaped to engage another wall of the nose to prevent upward movement of the base portion in the opening. The other tab, serves as a registration member to align the base portion in its desired longitudinal, vertical and angular orientation.
In other instances, the hollow, slotted needle does not include a knife element, the knife element being located elsewhere in the tagger gun so that the severable connector is cut by the knife element prior to the loading of the individual cross-bar into the hollow, slotted needle. Examples of tagger guns employing this type of arrangement include commonly-assigned U.S. Pat. Nos. 5,320,269 and 4,998,661, both of which are incorporated herein by reference.
Typically, the above-mentioned means for feeding an individual cross-bar through the hollow, slotted needle and the desired article of commerce comprises an elongated ejector rod or plunger which is insertable into the slot of the hollow, slotted needle and is movable along its longitudinal axis. Typically, the ejector rod is coupled to a triggering mechanism in the tagger gun so that, upon actuation of the triggering mechanism, the ejector rod engages the rear of a cross-bar and pushes it through the hollow, slotted needle and the desired article of commerce.
As can readily be appreciated, because the ejector rod is a movable part, opportunities exist for the ejector rod to malfunction (for example, by becoming jammed in the tagger gun, by becoming disengaged from the triggering mechanism, etc.).
In U.S. Pat. No. 3,900,925, inventor La Torraca, which issued Aug. 26, 1975, there is described a simplified integral button attacher without any moving parts. The attacher consists of a needle having a hollow slotted end terminating in a point for insertion of one end of an improved fastener and a gripping means, attached to the opposite end of the needle, for simultaneously pushing the fastener loaded needle through a button aperture and the fabric to which it is to be attached.